Scott Sio (born 16 October 1991 in Sydney, Australia) is an Australian rugby union player who plays for the Brumbies in Super Rugby. His playing position is prop. He made his Brumbies debut during the 2012 Super Rugby season against the Sharks in Canberra.
Sio also represented Australia under 20 at the 2011 IRB Junior World Championship. He was educated at Sydney's Trinity Grammar School in Summer Hill, here he attained the roles of Captain of Rugby and School Vice-Captain in 2009. Later that year, he represented NSW Schoolboys, Australia A Schoolboys and Australian Schoolboys.
He was named in the Wallabies 31-man Squad to take on the British and Irish Lions in their three test series. Despite being named in the squad, he was allowed to play in the Brumbies game against the Lions, performing admirably, to become the first Australian provincial side to defeat the Lions in 42 years.
Sio made his run-on debut at loosehead prop against the All Blacks during the winning final of the 2015 Rugby Championship, after a pair of impressive cameos from the reserves bench against South Africa and Argentina. Sio was named in the Wallabies 31-man squad for the 2015 Rugby World Cup, where he supplanted most-capped Wallabies prop James Slipper as the Wallabies first choice loosehead. He currently is now a regular in the Wallabies starting XV at loosehead prop.
He is son of the former Samoan prop David Sio, who played in the 1991 Rugby World Cup and also the cousin of up and coming player Fereti Sa'aga who has also represented Australia on the Junior stage.
As of 22 July 2016